Normally the inflation of a tire after fitting onto a wheel-rim is carried out by placing the wheel onto a supporting platform (usually the rotating platform of a wheel fitting machine) and blowing compressed air into a tire through the suitable inflation valve.
As the pressures involved can be relatively high, if for any reason the tire bursts, shreds of the tire and under extreme circumstances the wheel-rim itself would be thrown upwards, dramatically jeopardizing the operator's safety.
Until now attempts have been made to limit such a risk by resorting to devices e.g. inflation cages. Inflation cages are themselves very effective devices, but they have the drawback to be rather cumbersome and difficult to use, as it is necessary to transfer the tire into a cage (usually manually, thus with a certain effort). The poor practicality of such devices and above all the inertia or laziness of the operator get him to give up using them as he should, with the practical result that he is often exposed to serious safety hazards.